Starter control switch



May 11, 1954 L. C. DERMOND ET AL STARTER CONTROL SWITCH Filed June 26, 1952 INVENTORS 3 war/(c: c. ommma BY CRAIG u HOBTON THE/R ATTMIIHJ Patented May 11, 1954 STARTER CONTROL SWITCH Lawrence C. Dermond, Rochester, N. Y., and Craig V. Morton, Dayton, Ohio, assignors to General Motors Corporation, Detroit, Mich., a corporation of Delaware Application June 26, 1952, Serial No. 295,752

16 Claims.

This invention relates to switches, designed to be used in a control system for the starting apparatus of an internal combustion engine, which are of the semi-automatic type that are manually opened and closed to effect energizationand deenergization of the starting motor, but which are provided with means automatically operated to prevent closing of the switch at any time while the engine is operating under its own power, and more particularly to a switch of the type referred to which is opened and closed in response to movements of the carburetor throttle.

It is the principal object of the present invention to provide a switch of the type referred to which is of novel construction, is inexpensive to manufacture and in which the closing and opening of the switch is brought about by opening and closing movements of the throttle and through the medium of mechanism which is effective to close the switch with a snap action when the throttle is opened and to hold the switch closed until the throttle is returned substantially to its normal closed or idle position. It has been found that by closing a switch of this kind with a snap action pitting of the contacts is considerably reduced and the switch of the present invention is a simple and inexpensive device for effecting closing of the switch contacts in this manner.

Further objects and advantages of the present invention will be apparent from the following ole scription, reference being had to the accompanying drawings wherein a preferred embodiment of the present invention is clearly shown.

In the drawing:

Fig. l. is a vertical section through a switch constructed in accordance with the present invention.

Fig. 2 is a fragmentary section on the same line as Fig. l, but with the parts in different position. Fig. 3 is a section on the line 3-3 of Fig.1.

The starter control system, in which the switch disclosed and claimed herein is particularly designed to be used, is not illustrated since the system is not being claimed herein, but the sys tem is fully disclosed in applicants co-pending application Serial No. 267,151, filed January 22. 1952, and includes the switch it which is of different construction than that disclosed, but closes a control circuit to effect energization of the starting motor. The circuit controlled by the switch which is the subject of the present invent on may be the same as that shown. This circuit includes two leads l and 2 which are electrically connected with the fixed and movable contacts 3 and 4 respectively, and when the latter are in engagement the starting motor is energized but when separated the starting motor is inoperative. The fixed contact 3 is secured to a vertical metal bar 5 which is in conductive relation with a binding post 6 to which the lead I is suitably connected, while the movable contact 4 is carried by a metal bar l which is suitably pivoted at its lower end on a supporting bar 8 electrically connected to a binding post i! with which the lead 2 is connected.

The contacts 3 and d are positioned within a housing it, the vertical wall it of which is flat and is secured in a desirable way to a fiat surface 12, formed on the mixture outlet i3 of the carburetor, the flange M of which is adapted to be secured to the intake manifold of the engine in the conventional manner. Positioned in the intake passage and movable to diiferent positions therein to control the quantity of combustible mixture supplied to the engine is the throttle valve !5 which is secured in any suitable way to the shaft [6 adapted to be opened and closed by the usual foot operated accelerator pedal to control the engine speed. As seen in Fig. 1, shaft I6 rotates counter-clockwise to open the throttle and vice versa.

The throttle shaft I6 is suitably mounted for rotation in the carburetor outlet l3 and one end thereof extends through the wall of such outlet and also through the wall ll into the housing H) as best shown in Fig. 3. Secured in any desirable way on a part ll of shaft [8 which projects into the housing Ill and may be, as shown, slightly smaller in size than the main body of the shaft 16, is an arm I8 and suitably secured in an orifice near the outer end of such arm is a pin l9 which extends parallel to the shaft it for a purpose more fully set forth later. As shown, the arm is is press-fitted on a knurled surface I! of the shaft it, but may be secured to the shaft in any other suitable way. Received on a further reduced portion 2| of the shaft l6, isa cam member 23 of insulating material, which is positioned between a shoulder 22 and the enlarged end 2d of the shaft, and is rotatable on the shaft. A torsion spring 25 surrounds the shaft between arm 18 and cam 23, one end 25 of such spring extending through a hole in the arm is and the other end 2? entering a hole in the cam 23, so that rotation of the throttle shaft tends to rotate the cam 23 through the medium of this spring.

Normally, when the engine is not running, the cam is free to move and is rotated by the rotation of the throttle shaft. As the throttle is moved toward open position, the shaft l6 and arm [8 are rotated in a clockwise direction which results in putting the spring 25 under additional tension and, through the medium of such spring, rotating cam 23 in a clockwise direction, as seen in Fig. 1. As the cam 23 is rotated, the cam lobe 28 thereon engages the enlarged head 29 of a pin 38 and moves such pin to the right as seen in Fig. 1, such movement of pin 30 bringing about the closing of the switch contacts 4 and 3 in a manner described more fully later. The pin 30 extends through a hole in the closed end of a cylinder 3i which is slidable in a recess formed in a boss which extends inwardly from the wall of housing it, a spring 33 serving to urge the cylinder 3i toward the left. The pin 30 is held in fixed relation to the cylinder 3| by means of a flange 34: and the enlarged head 35 formed on the pin on opposite sides of the closed end of said cylinder. The pin 3%] extends through an opening 36 in the bar I of smaller diameter than the head 29.

The bar 3' is part of a toggle mechanism which is effective to close the switch contacts with a snap action when the pin 30 is moved to the right by the cam 23. The contact 4 is carried by a tongue 3'! cut out of the bar I and immediately above the tongue the bar has secured thereto, in any desirable way, a cup-shaped element 38 which receives the lower end of a helical spring 39, the upper end of which is received in a cup-shaped piece of insulating material 40 positioned in a recess in the wall of housing Iii. Normally, when the engine is not in operation, the cam 23, the bar 7, pin to and associated parts are in the position shown in Fig. 1 and the cam is free to move. In such position, the bar "I is held against a fixed stop rod at which extends across the housing it by both the springs 33 and 39 and in this position the bar i is a little to the left of dead center. As the pin 30 is moved to the right upon opening of the throttle, it first moves the cylinder 3| to the right sufficiently to permit movement of bar 1 far enough to the right to engage contacts 4 and 3 without striking the end of cylinder 3|, this movement also compressing the spring 33. During the final part of the movement of pin 30 to the right, the head 29 engages bar I moving it to the right and, as soon as it passes dead center position, the spring 39 snaps the contact 4 into engagement with the contact 3.

When the engine has started, the throttle is moved to closed position with accompanying movement of the arm H3 in a clockwise direction.

During this movement, the pin I9 engages a lug 42 projecting from the surface of cam 23, so that the cam is positively moved in a clockwise direction to its original position. As the cam is moved in this manner, the spring 33 expands, the end of cylinder 35 engages the bar 1 and moves it to its original position against stop 4|, the spring 33 exerting a greater force on the bar 1 than does spring 3Q. Since the spring 33 is the stronger spring, it has to be compressed manually in order to permit the snap movement of contact 4 by spring 39.

As stated previously, the cam 23 is free to move when the engine is not running, but when the engine is in operation, the cam is positively held against movement so that closing of the switch contacts is prevented during engine operation. This is necessary because any operation of the starting motor during the running of the engine would result in serious damage. For this purpose the cam has a shoulder 43 which is engaged when the engine is running by the arm 44 of a lever pivoted on a pin 45 secured in the housing to and having another arm 46 which is pivotally connected to a link 41, pivoted on a pin 48 carried by a piston 49 of either suitable plastic material, as shown, or metal and slidable in a cylinder 53 formed in the housing In. The normal position of the lever arm 44 is shown in Fig. 2 and the position of such arm when the engine is running is shown in Fig. 1.

Normally, the piston 49 is held in a position low enough to hold the arm 44 out of the path of movement of shoulder 43 by a spring 5| positioned above the piston 49 in a bore 52 formed in the wall of the housing H]. A passage 53 connects with the bore 52 and with a conduit which leads to the engine intake posterior to the throttle. A sealing washer 54 of any suitable material is held in place by a split ring 55 and is engaged by a circular flange 56 on the top of piston. Engagement of the flange and seal washer substantially prevents entry of air into space 52 and enables the piston 49 to be held in its upper position by less suction than is required to lift the piston to its upper position.

The lower or normal position of the piston may be determined in any suitable way. For example, a stop rod 5? may extend across the housing iii under the lever arm 46 so as to stop the downward movement of the piston 39 when engaged by the arm 46.

Due to the sealing action of the washer 54, the suction effective on the piston 49 is always sufficient to hold the piston in its upper position during self-operation of the engine, but even if, due to any unexpected circumstance, the suction should fall below that required for this purpose, the cam shoulder 43 is urged against the end of arm 44 by the spring 25 and the friction between these parts will prevent any possible disengagement of the arm from such shoulder.

While the embodiment of the present invention as herein disclosed, constitutes a preferred form, it is to be understood that other forms might be adopted.

What is claimed is as follows:

1. In an electric starting apparatus for an internal combustion engine, control switch for controlling the operation of said apparatus and having, in combination, fixed and movable contacts which, when closed, cause said apparatus to become operative and when opened, render such apparatus inoperative, a toggle mechanism for closing said contacts with a action when the toggle is broke said toggle mechanism being normally in a position to hold the switch open, a carburetor throttle adapted to be opened and closed to regulate the quantity of combustible mixture supplied. to the engine, means operated by said throttle upon opening movement thereof to break said toggle and cause the closing of contacts and means operable upon movement of the throttle to closed position to restore the toggle mechanism to normal position and to effect dis-- engagement of said contacts.

2. In an electric starting apparatus for an internal combustion engine, a control switch for controlling the operation of said apparatus and having, in combination, fixed and movablecontacts which, when closed, cause said apparatus to become operative and when opened, render such apparatus inoperative, a toggle mechanism for closing said contacts with a snap action when the toggle is broken, said toggle mechanism being normally in a position to hold the switch open,

closed to regulate the quantity of combustible mixture supplied to the engine, means operated by said. throttle upon openingmovement thereof to break said toggle and cause the closing of said contacts and resilient means operable upon movement of the throttle to closed position to restore the toggle mechanism to its normal position and to effect disengagement of said contacts.

3. In an electric starting apparatus for an internal combustion engine, a control switch for controllin the operation of said apparatus and. having, in combination, fixed and movable contacts which, when closed, cause said apparatus to become operative and when opened, render such apparatus inoperative, a toggle mechanism for closing said contacts with a snapaction when the toggle is broken, said toggle mechanism being normally a position to hold the switch open, a carburetor throttle adapted to be opened and closed to regulate the quantity of combustible mixture supplied to the engine, means operated by said throttle upon opening movement thereof to break said toggle cause the closing of said contacts anti resilieo means operable upon movement oi the throttle to closed position to restore the toggle mechanism to its normal posi tion and to effect disengagement of said contacts, said resilient means being prevented from either restoring the toggle or disengaging the contacts L until the throttle has reached a predetermined closed position.

4. In an electric starting apparatus for an in-- ternal combustion engine, a control switch for controlling the operation of said apparatus and having, in combination, lined and movable contacts which, when closed, cause said apparatus to become 0,? and, when. opened, render such apparatus inoperative, a toggle mechanism for closing said contacts with a snap action when the toggle is broken, resilient means normally holding the toggle mechanism in a position. to

hold the switch open, carburetor throttle adapted to be opened and closed to regulate the quantity of combustible mixture supplied to the engine, and a member operated by said throttle upon opening movement thereof to render said resilient ineffective and to break the toggle-so to bring about closing of said switch, said member being operable upon movement of the throttle to closed position to render said re silient effective to move the toggle to its original inoperative position.

5. In an electric starting apparatus for an internal combustion engine, a control switch-for controlling the operation. of said apparatus and having, in col ination, fixed and movable contacts which, lien closed, cause said apparatus to become operative cl, when opened, render such apparatus inoperctive, a toggle mechanism for closing said contacts with a snap action when the toggle is broken, a carburetor throttle secured to a rotatable sLait and movable to different positions to vary, the quantity of combustible mixture supplied to the engine, a member supported on the throttle shaft operable upon opening movem nt of the throttle to break the toggle and bring about closing oi'the switch, means operable upon movement of the throttle to closed position to restore the toggle to its original inoperative position and effect opening oi. the switch.

5. In an electric starting apparatus for an internal combustion engine, a control switch for controlling the operation of said apparatus and having, incombination, fixed and movable to become operative and when opened, render such apparatus inoperative, a toggle mechanism for closing said contacts with a snap action when the toggle is broken, resilient means normally holding the toggle mechanism in a position to hold the switch open, a carburetor throttle secured to a rotatable and movable to different positions to vary the quantity of combustible mixture supplied. to the engine and a member supported on the throttle shaft and operable u on ope ing movement of the throttle to render said resilient means ineffective and to break the toggle so to bring about closing of the switch, said member being operable upon movement of i ethrcttle to closed position to render said reeffective to move the to its ginl inoperative position and open the switch. Z. In an electric starting apparatus for an internal combustion on ine, a control switch for controlling the operation of said apparatus and having, in combination, and movable contacts which, when closed, cause said apparatus to become operative and. opened, render such apparatus inoperative, a toggle mechanism for closi said contacts with a snap action when the tog is is broken, a carburetor throttle secured to a rotatable shaft and movable to different positions to vary the quantity of combustibl mixture supplier"; to the engine, a member supported on the throttle shaft anrl operable upon a predetermined opening movement of the throttle to break the toggle bring about closing of said switch and means operable upon movement of the throttle to closed position to restore the toggle to its original inoperative position and effect opening of the switch, said member being effective to prevent opening of the switch by said last named means when the throttle is open to an extent equal to or more than said predetermined movement.

8. In electric starting apparatus for an internal. combustion engine, a control switch for controlling the operation of said apparatus and having, in combination, fixed and movable contacts, which, when closed, cause said apparatus to become operative when opened, render such apparatus inoperative, toggle mechanism for closing said co t acts with snap action when the toggle is broken, a carburetor throttle secured. to a rotatable shaft and movable to different positions to vary the quantity of combustible mixture supplied to the engine, a cam supported on the throttle shaft and operable upon a predetermined opening movement of the throttle to break the toggle and bring about closing of said switch, operable upon movement or the throttle to closed position to restore the toggle to its normal inoperative position and effect opening of the switch, said cam being so formed. that prevents opening of the switch by said last named means when the throttle is open to extent equal to or more than said predetermined movement.

9. In an electric starting apparatus for an internal combustion en no, a control switch for controlling the operation of said apparatus and having, in combination, fixed and movable contacts which, when closed, cause said apparatus to become operative and when opened, render such apparatus inopera" inechanisu for closing said contacts v. 1th a snap action when the toggle is broken, resilient means normally holding the toggle mechanism in a position to .hold the switch open, a carburetor throttle valve secured to a rotatable shaft and movable to dif- ,ferent positions to vary the quantity of combus- 'tible mixture supplied to the engine, and a cam carried by the throttle shaft and operable upon :a predetermined opening movement of the thr0ttie to render said resilient means ineffective and to break the toggle so as to bring about closing of the switch, said cam being also eilective upon movement of the throttle to closed position to render resilient means eilective to restore the toggle to its original position and open the switch and said cam being so formed as to prevent operation of said res i-cnt as long as, the throttle is to an extent equal to or greater than said predetermined opening movement.

ill. In an electric sta ting apparatus for an internal combination e a control switch for controlling the operation of said apparatus and having n combinatio and movable contacts which, when closed, cause said apparatus to become operative nd, when opened, render such e mechanism supspring operative a snap action to close sch the tog 'le moved beyond dead center in one direction, stronger spring normally preventing operation. or" the toggle by the first spring in a direction to close the switch,

. a to the engi means operable b the throttle upon openi' movement thereof to move sail; s lg to position where it is ineilective to o a movement of the toggle to switch posiion and for moving the toggle beyond center pos .ul'i a switch closing direction.

11, In elect c starting apparatus for an internal combustion. a control switch for control ing: the oper tion or apparatus and having, f combinati n, and movable contacts which, when cl eel cause :3 id apparatus to operative in n opened, render such apparatus inoperative, a mechanism supporting movable contact, a spring operative to move the toggle with action to close n. one c s ction, a second stronger spring normally preven ing operation of the toggle by the first in a direction to close the switch. a carburetor throttle movable to different positions to vary quantity of cornbu M tible infvturc supplied to the engine, means operby the throttle upon opening movement ther of to move second to a position where it ir effective to movement of the toggle swi 0 closing position and for moving the toggle beyo d dead center position in a switch .ction, said last named means being en throttle is moved to closed g about operation of said second spring to move the toggle to its original position and effect opening of the switch.

12. In. an electric starting apparatus for an internal combustion engine, control switch for controlling the operation of said apparatus and having, in. combination, fixed. and movable contacts which, when closed, cause apparatus to become operative and, when opened, render such apparatus inoperative, a toggle mechanism including a pivoted bar supporting said movable contact, a spring operative to move said bar with a snap action to close the switch when said bar is moved beyond dead center in a switch closing h when th is moved beyond direction, a second stronger spring, means movable thereby into engagement with said. bar to hold the bar in a position when the switch is open, a member operable to move said last named means to a position where it will not be engaged by said bar during movement of the latter to switch closing position also eirective to move said bar beyond dead center position in a switch closing direction, a carburetor throttle movable to different positions to vary the quantity of combustible mixture supplied to the engine, a second member operable by the throttle during opening movement thereof for operating said first member to effect movement of said bar and closing of the switch.

13. In an electric starting apparatus for an internal combustion engine, a control switch for controlling the operation of said apparatus and. having, in combination, fixed and movable contacts which, when closed, cause said apparatus to become operative and, when opened, render such apparatus inoperative, a toggle mechanism including a pivoted bar supporting said movable contact, a spring operative to move said bar with a snap action to close the switch when said bar is moved beyond dead center in a switch closing direction, a second stronger spring, means movable thereby into engagement with said bar to hold the bar in a position when the switch is open, a member operable to move said last named means to a position where it will not be engaged by said bar during movement of the latter to switch closing position and also effective to move said bar beyond dead center position in a switch closing direction, a carburetor throttle movable to different positions to vary the quantity of combustible mixture supplied to the engine, a second member movable by the throttle into position to engage and move said first member to eiiect movement of said bar and closing of the switch, said second member being moved, upon movement of said throttle to closed position, out of engagement with the first member to permit movement of the toggle bar to normal position and. opening of the switch by said second spring.

14. In an electric starting apparatus for an internal combustion engine, a control switch for controlling the operation of said apparatus and having, in combination, fixed and movable contacts which, when closed, cause said apparatus to become operative and when opened, render such apparatus inoperative, a toggle mechanism for closing said contacts with a snap action when the toggle is broken, said toggle mechanism being normally in a position to hold the switch open, a carburetor throttle adapted to be opened and closed to regulate the quantity of combustible mixture supplied to the engine, means operated by said throttle upon opening movement thereof to break said toggle and. ca the closing of said contacts and means oper e during self-operation of the engine to prevent operation of said throttle operated means.

15. In an electric starting apparatus for an internal combustion engine, a control switch for controlling the operation of said apparatus and having, in combination, fixed and movable contacts which, when closed, cause said apparatus to become operative and when opened, render such apparatus inoperative, a toggle mechanism for closing said contacts with a snap action when the toggle is broken, said toggle mechanism being normally in a position to hold the switch open, a carburetor throttle adapted to be opened and closed to regulate the quantity of combustible mixture supplied to the engine, means operated by said throttle upon opening movement thereof to break said toggle and cause the closing of said contacts, means operable upon movement of the throttle to closed position to restore the toggle mechanism to normal postion and open the switch and means operable by engine suction to prevent operation of said throttle operated means during self-operation of the engine.

16. In an electric starting apparatus for an internal combustion engine, a control switch for controlling the operation of said apparatus and having, in combination, fixed and movable contacts which, when closed, cause said apparatus to become operative and when opened, render such apparatus inoperative, a toggle mechanism for closing. said contacts with a snap action when the toggle is broken, resilient means normally holding the toggle mechanism in a position to hold the switch open, a carburetor throttle secured to a rotatable shaft and movable to different positions to vary the quantity of combustible mixture supplied to the engine and a member supported on the throttle shaft and operable upon opening movement of the throttle to render said resilient means ineffective and to break the toggle so as to bring about closing of the switch, and means operable by engine suction to prevent operation of said throttle operated member during self-operation of the engine.

References Cited in the file of this patent UNITED STATES PATENTS Number 

